Electric furnace



(No Model.) 2 Sheets-Sheet 1.

W. S. HORRY.

ELEGTRIG FURNACE.

No. 597,880. Patented Jan. 25, 1898.

mwakmm 3 Wsuwm m2 mails PETERS co. PHOTO-LXTH WASHINGTON. a. c,

U ITED STATES PATENT OFFICE.

\VILLIAM SMITH HORRY, OF SAULT STE. MARIE, MICHIGAN.

ELECTRIC FURNACE.

SPECIFICATION forming part of Letters Patent No. 597,880, dated January25, 1898.

Application filed April 16, 1897. serial No. 632,418. (No model.)

To all whom it may concern:

Be it known that I, WILLIAM SMITH HORRY, a subject of Her Majesty theQueen of Great Britain, residing at Sault'Ste. Marie, Michigan, haveinvented a new and useful Electric Furnace, of which the following is aspecification.

The action of a comparatively high degree of heat upon a mixture of cokeand lime results in the production of 'carbid of calcium. Variouselectric furnaces have been devised for efiecting such union ofelements. Generally the furnace consists of an iron bedplate, whichconstitutes the lower electrode or pole, and a large piece of carbon,which forms the other pole and can be raised or lowered. hen theelectric arc is struck be tween these poles, a mixture of coke and limeis fed in, and the resulting carbid of calcium piles up and becomeshigher on the bed-plate,

the upper carbon being raised to make room for it. After this has goneon for some time the imperfections of such a furnace become evident. Thevoltage between the poles decreases, because the electrical resistanceof the pile of carbid differs from the electrical resistance of theingredients which form it. There is then a mass of carbid to heat upbesides the heat required for generating the arc and fusing additionalmaterial. The former is entirely wasted and positively deleterious,because it causes the carbid to liquefy and run, so as frequently tomelt the iron of the bed-plate. By reason of this waste the current isturned off after a few hours, and the whole furnace has then to becleaned out and again started, and in cleaning out the furnace all theheat, instead of being preserved, is dissipated, because the apparatusis allowed to cool down. More recently an iron crucible has beenemployed instead of the bed-plate. Its use effects a saving of time incleaning out the furnace, but it adds to the weight to be removed and isnot an improvement in principle.

Objects of my invention are to obviate the above-mentioned defects anddisadvantages, to economize heat, to adapt the furnace to the practiceof a continuous process, to produce uniform quality in the finishedproduct, to avoid undue waste of material, to keep the current uniform,and to obviate the necessity for special types of carbon-holders.

In my invention use is made of means for producing an electric are whichis fixed, or, in other words, not moved in respect to the furnace, of arotatable receptacle for the fused materials, and of means for slowlyshifting said movable receptacle.

My invention consists of the improvements hereinafter described andclaimed.

The nature, characteristic features, and scope of my invention will bemore fully understood from the following description, taken inconnection with the accompanying drawings, forming a part hereof, and inwhich- Figure 1 is a side elevational view illustrating an electricfurnace embodying what I believe to be the best means for practicing myinvention. Fig. 2 is a sectional view taken on the line 2 2 of Fig. 1,and Fig. 3 is a detached view of one of the plates or covers shown inFigs. 1 and 2.

In a machine of my invention there are means for producing an are whichremains in one position and is not shifted about or drawn out. a aindicate such means and comprise, for the sake of illustration, carbonssuitably connected with the terminals a of an electric system. As shown,the adjacent ends of these carbons are beveled, so as to form a verticalpassage, as 6, between them, across which the arc is formed and throughwhich the material to be treated is passed. There is present in amachine of my invention also a movable receptacle for the fusedmaterial. 0 designates such a receptacle and comprises a spool-likestructure revolubly mounted in suitable supports, standards, or framesd. This receptacle 0 is provided with means for shifting it. Thehand-wheel c, worm e, and worm-wheel e attached to the receptacle 0, aresuch means.

f are removable or detachable cover-plates which may be provided withlips, as f, by which the plates are made to overlap each other and haveprojections, as f fitted to the flanges or heads of the receptacle 0.

g are means, as bolts or clips, by which the plates or covers f may bedetachably applied to portions of the periphery of the receptacle c.

present, to rise.

h is a bottomless hopper suitably supported, for example, by pivoting orotherwise attaching it to the standards d and permitting it to hangbetween the flanges of and within the receptacle 0. As shown in thedrawings, this hopper is fitted with fire-clay, as at h, and withfire-brick, as at 71 Other fire-resisting material may be used, and itconstitutes simple and efficient means for insulating either or both ofthe electrodes and for supporting either or both of them withoutrequiring the use of special clamps or holders. Moreover, the connectionbetween the carbon and electrical conductor may be of simpleconstruction because it is placed away from the heated parts of thefurnace.

The mode of operation of my invention may be described in connectionwith the foregoing apparatus as follows: Upon closing the circuit thecurrent traverses the spaced) and acts upon the materials, as carbon andlime, of which a supply is placed in the hopper h, and gradually passingthrough the space 1) reaches the receptacle 0. In thus traversing thefurnace, or, more accurately, the portion thereof designated 1), thematerials become highly heated, and in the case of lime and carbon ortheir equivalents carbid of calcium is formed, which builds upimmediately under the carbon, lowers the electrical resistance, andcauses the ampere meter a if The attendant upon seeing this operates thewheel a or otherwise rotates or shifts the receptacle 0 in the directionindicated by the arrow in Fig. 1. By this motion carbid is removed awayfrom the arc or space designated 1) and fresh material sinks from thehopper into its place ready to be acted upon in like manner. Aftercontinuing the process for some time another plate f should be added tothe receptacle at substantially the point designated F in Fig. 1 inorder to retain the material in the receptacle, and fresh supplies mustfrom time to time and slowly be fed into the hopper h during theoperation of the furnace. The carbid is formed in the shape of a ring orpart of a ring, and when it has become so long that it might interferewith the carbon at or other part of the furnace, it being by this timecool, it can be broken off and removed, some of the plates f at theright-hand portion of the furnace being taken oif, if necessary, forthis purpose. The production of carbid or other operation adapted to thefurnace can in this manner go on indefinitely,cr,at least,until thecarbons are entirely consumed. This furnace affords means for producingcalcium carbid in one continuous piece, and it also possessesv teriallyin quality, being poor at the bottom of the furnace and rich in themiddle and again poor at the top; also, such old furnaces had thedisadvantage of entailing a considerable waste of material, acomparatively large amount of coke and lime being caked together in sucha manner that they could not again be used unless reground and remixed.Such defects are absent from the furnace of my invention. Anotheradvantage is that in my furnace there are no heavy weights to lift.

The greatest advantage incident to the use of my furnace has relation tothe electrical machinery. In the old furnaces the demands on theelectrical generator were very variable for an hour or more after thefurnace was started,whereas in a furnace of my invention the load on theelectrical generator is constant and the advantage is very marked.

It willbe obvious to those skilled in the art to which myinventionappertains that modifications may be made in details without departingfrom the spirit thereof. Hence I do not limit myself to the preciseconstruction .and arrangement of parts hereinabove set forth, andillustrated in the accompanying drawings; but,

Having thus described the nature and objects of my invention, what vIclaim as new, and desire to secure by Letters Patent, is

An electric furnace comprising the combination of a bottomless hopper,electrodes supported on the walls of said hopper, circuit connectionsfor the electrodes, a rotatable receptacle arranged below said hopper,and plates removably applied to the periphery of said receptacle,substantially as described.

In testimony whereof I have hereunto signed my name.

WILLIAM SMITH HORRY.

In presence of JOHN MCNAUGHTON, WILLIAM M. DANFORTH.

